I found an Easter Egg in Deltarune Chapter 1. If you go back to the Save Point in front of Sean's Shop after defeating King Round, you are given this dialogue instead
Names | Undertale Wiki | Fandom
Deltarune Chapter 1 Is Really Good And You Should Play It – TATLER
Deltarune: What Happens if you Enter in Certain Names at the Beginning of Game - Mae Polzine
Deltarune Name Easter Egg - YouTube
Names | Undertale Wiki | Fandom
DELTA RUNE - NAME EASTER EGGS & SECRETS - YouTube
DELTARUNE (UNDERTALE 2) - Naming your character KRIS - YouTube
Just realized that he says ”40 G” (the currency in undertale instead of ”40 D” (the currency in deltarune). Easter egg? : r/Deltarune
Stream Deltarune - Don't Say His Name by West. N. | Listen online for free on SoundCloud
All Gaster SECRETS in Deltarune! (Deltarune secrets) - YouTube
If you guys didn't know, there is a secret easter egg inside the oven of the pizza restaurant. : r/Deltarune
Deltarune: What Happens if you Enter in Certain Names at the Beginning of Game - Mae Polzine